This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goal of this proposal is to build upon the current knowledge of rehabilitation and neuroimaging by examining for the first time the relationship between cardiorespiratory fitness and brain activity in traumatically brain injured (TBI) human subjects. The primary objectives of this study are to identify differences in the cortical activity of TBI subjects compared to normal control subjects during a working memory task and to ascertain the effect of participating in a 12 week aerobic exercise program on that cortical activity. There is both theoretical and practical significance for conducting this study. On a theoretical level, this study will integrate exercise science and neuroscience to enhance the understanding of the distant effects of cardiorespiratory fitness beyond the commonly acknowledged physiological effects. From a practical and therapeutic perspective, knowing whether the benefits of aerobic exercise already seen within well and impaired animals and healthy human populations applies to brain-injured adults may eventually lead to the clinical use of aerobic training programs as efficacious adjuncts to cognitive rehabilitation following TBI.